With the known types of plastic and cork bottle stoppers for bottles containing carbonated wines and the like, a problem exists in the removal of the stopper from the bottle neck either too readily or, in some instances, the stopper is so tightly held in the bottle neck that removal of the stopper is very difficult. The inability of mechanical glass blowing machines to hold close tolerances for the neck bore dimension of the bottle is usually the cause of this problem. Where the cork or plastic stopper is held in the neck bore of a bottle by a conventional wire cage, removal of the cage can result in the stopper being ejected from the bottle at a dangerous velocity causing bodily injury and/or property damage. The velocity at which the stopper is ejected is dependent upon the degree of compression of the stopper in the neck bore and the type of bottled carbonated beverage.
The threaded bottle stopper according to this invention overcomes the above problems by providing a stopper which has a mechanical assist for overcoming the frictional fit of the stopper in the neck bore to assist in removing the stopper and simultaneously control the release of pressurized gases from the bottle to reduce the possibility of the stopper being ejected from the bottle at a dangerous velocity. The threaded bottle stopper may be made from a thermoplastic resin having the desired memory to permit a compression fit of the stopper in the neck bore of the bottle. The threaded bottle stopper comprises a cap having a disc portion with an annular skirt depending downwardly therefrom. A tubular body portion extends downwardly from and integral with the underside of the disc portion. A continuous thread is provided on the inside surface of the annular skirt. The outside diameter of the tubular body portion is of a dimension which permits insertion thereof within the neck bore of a bottle. The continuous thread on the annular skirt engages a continuous thread on the neck of the bottle so that rotation of the threaded bottle stopper about its longitudinal axis in either direction, moves the tubular body portion respectively into and out of the neck bore of the bottle. The bottle stopper has means for sealing the discharge opening of the bottle neck.
The tubular body portion of the threaded bottle stopper has gas release means provided on the outside surface thereof for controlling the release of pressurized gases from the bottle. The gas release means comprises at least one open-ended tortuous channel through which the pressurized gases pass before escaping to the atmosphere. The gas release means is operable to release pressurized gases from the bottle while the continuous thread on the annular skirt remains in engagement with the external thread of the externally threaded bottle neck. The release of the gas is, of course, subsequent to the breaking of the sealing means which is caused by rotation of the threaded bottle stopper in the respective direction to withdraw the tubular body portion from the neck bore of the bottle.
The gas release means may consist of a single spiral thread provided on the outside surface of the tubular body portion. The thickness of the thread ridge is such to permit sliding contact between the thread ridge and the inside surface of the neck bore of the bottle. The single spiral thread is shaped to define an open-ended spiral-shaped channel.
The open-ended tortuous channel is so positioned on the outside surface of the tubular body portion that communication of the channel with the atmosphere is complete prior to disengagement of the continuous thread on the inside surface of the annular skirt with the threaded neck portion of the bottle so that the release of the pressurized gases cannot eject the stopper from the bottle at a dangerous velocity.
The release of the pressurized gases from the bottle is controlled by a preselected cross-sectional area for the open-ended channel to ensure that a portion of the pressurized gases remain in the bottle a short time after the initial release of gases from the bottle so that a complete removal of the bottle stopper from the bottle neck results in the familiar and very desirable "pop" sound thereby indicating to the consumer that the contents are fit for consumption.
Since the threaded bottle stopper provides a mechanical assist for withdrawing the tubular body portion from the neck bore of a wine bottle, the bottle stopper may be slightly oversized to ensure that the neck bore is properly sealed thereby alleviating the need to closely control the neck bore tolerances of glass blown bottles.